The court holds that the damages are not the type of damages that would occur in the ordinary course of things as the probable result of a delay in delivery of a telegram. This means they are not general damages (which are just defined as damages that occur in the ordinary course of things). The only alternative is that the damages were caused by special circumstances. That is, they are special damages.
Note that the loss of money on the 1,000 bags is special damages even if the telegraph company did not have reason to know about the special circumstances. That knowledge is relevant to whether the damages were reasonably foreseeable, not to whether they get categorized as special damages.
Let's turn to the question of whether these special damages were foreseeable.